Here is the full list of all 24 Learn Japanese To Survive! Katakana War achievements.
Maximize all character's affection levels.
Clear the game.
Complete all 20 side quests.
Obtain the ultimate sword.
Complete 15 side quests.
Try 3 different types of seafood.
Unlock the potential of corn soup.
Complete lesson 10.
Complete lesson 9.
Complete lesson 8.
Complete lesson 7.
Maximize a character's affection level.
Complete 10 side quests.
Complete lesson 6.
Complete lesson 5.
Visit the Challenge Castle.
Complete 5 side quests.
Complete lesson 4.
Unlock the power of the Crystarium
Complete lesson 3.
View a character's affection event.
Complete a side quest.
Complete lesson 2.
Complete lesson 1.